Flower of Commicarpus pentandrus showing the upper, petaloid part (a) and the lower, coriaceous part (b). White arrow indicates the glands around the apex of the lower part of the fl ower and the black arrow the longitudinal grooves. Scale bar 2 mm. 

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Context 1

... inflorescence in Commicarpus is an umbel, sometimes with up to four whorls together in the same inflorescence. The peduncles are 20- 150 mm long (Table 1). The flowers of Commicarpus are infundibiliform (Fig. 3). The flowers can be divided into two parts, an upper petaloid part and a distinct lower, coriaceous part (Fig. 4). The upper petaloid part has white, pink or purple flavonoid pigmentation and is 2-17 mm long (Table 1). The lower, coriaceous part of the flower is 2-7 mm long and can be cylindrical (C. chinensis subsp. natalensis, C. fallacissimus and C. plumbagineus var. plumbagineus), clavate (C. decipiens and C. pentandrus) or elliptic (C. ...

Context 2

... Standl., a genus of about 30 – 35 species, is distributed throughout the tropical and subtropical regions of the world, especially in Africa and western Asia (Douglas and Spellenberg, 2010). With 12 species, northeastern Africa and southern Arabia are the center of diversity for the genus (Thulin, 1990). Members of Commicarpus have a preference for arid environments, exempli fi ed by their clustering in Somalia, Ethiopia and adjacent parts of southern Arabia. In southern Africa a secondary center of diversity, eight species, are con fi ned to the arid parts of Botswana, Namibia and South Africa (Meikle, 1978). Members of Commicarpus are morphologically similar to those of Boerhavia and the genus was originally treated as a section of Boerhavia ( Boerhavia sect. Adenophorae Heimerl; Heimerl, 1889). This classi fi cation was followed until 1909 when Standley separated the genus Commicarpus from Boerhavia due to differences in habit (scrambling or climbing in Commicarpus ; diffuse in Boerhavia ), structure of the fruit (10-ribbed with large viscid and mucilaginous glands in Commicarpus ; 3 – 5-winged or 5-ribbed with multicellular trichomes present or absent in Boerhavia ), and the shape of the perianth (funnel-shaped in Commicarpus ; bell-shaped in Boerhavia ). This distinc- tion was maintained until 1931 when Standley included Commicarpus in Boerhavia “ to aid in reducing ... the increasing number of genera ” , though he stated that he still believed in the validity of Commicarpus as a separate genus (Standley, 1931). Heimerl (1934), however, recognized Commicarpus as a separate genus. Fosberg (1978) reduced Commicarpus to a subgenus of Boerhavia , but this was not validly published (Harriman, 1999). Recent molecular studies (Douglas and Manos, 2007) have provided further evidence that Boerhavia and Commicarpus are indeed two separate, monophyletic genera. In southern Africa (Botswana, Lesotho, Namibia, South Africa and Swaziland), eight species of Commicarpus are recognized. These are widely distributed in the region with Namibia being the main center of diversity (Germishuizen and Meyer, 2003). The most recent revision of Commicarpus in southern Africa is that of Stannard (1988) for Flora Zambesiaca , although he only treated members of fi ve species, namely C. chinensis (L.) Heimerl subsp. natalensis Meikle, C. helenae (Roem. and Schult.) Meikle var. helenae , C . pentandrus (Burch.) Heimerl, C. pilosus (Heimerl) Meikle and C. plumbagineus (Cav.) Standl. var. plumbagineus . Commicarpus helenae var. helenae , C. pentandrus and C. plumbagineus var. plumbagineus were also treated in the Flora of Tropical East Africa (Whitehouse, 1996) and the Flora of Somalia (Thulin, 1993). Three currently-recognized species have not featured in any earlier treatments, and this has resulted in misidenti fi cations in the Flora of Southern Africa region (Struwig et al., 2011). This contribution is a fi rst attempt at a comprehensive taxonomic revision for the genus in southern Africa, and includes a key to the species, complete nomenclature, and a formal description of all the infrageneric taxa. Taxon accounts are supplemented with geographical distribution records, notes on the ecology, and known traditional uses. Red list assessments are also included. Plant material was collected during fi eld work in Namibia and South Africa. Specimens from the following southern African herbaria were studied: BLFU, BOL, GRA, J, KMG, KSAN, NBG, NH, NMB, NU, PRE, PRU, PUC, SAM, UCBG, UNIN, WIND and ZULU (acronyms according to Holmgren et al., 1990). Micrographs of the leaves were taken with a Canon 450D fi tted with a 100 mm Sigma macro lens. The length and breadth of the leaves as well as the length of the petiole were measured. Fresh fl oral material was collected in situ in 4% paraformaldehyde and fl owers taken from herbarium specimens were rehydrated for 10 min in boiling water. Three fl owers per species (one each from Namibia, Botswana and South Africa, where available) were dissected and the length of the peduncle, pedicel, upper and lower portions of the fl ower, stamens and ovary were measured. Mean length and width of anthocarps were determined by measuring ten herbarium specimens per species and three anthocarps per specimen (n = 30). Micrographs of the fl owers and anthocarps were taken with a Nikon Digital Camera DXM 1200F fi tted on a Nikon SMZ 1500 stereomicroscope. Morphological terminology follows Hickey and King (2000). Distribution records and habitat information were obtained from herbarium specimens as well as observations made during fi eld trips. Localities and species distribution patterns were mapped using ArcView 9.2 (ESRI, 2006). Information on the uses was gathered from herbarium label information, and a broad literature survey. Where fresh plant material was sampled, soil from the top 100 mm of the root zone of a plant was also collected. This was repeated for fi ve plants per population in 100 m 2 to make-up a composite soil sample for analysis. All soil samples were air dried and sent to Eco-Analytica for analysis (North-West University, Potchefstroom). Soils were analyzed for cation exchange capacity (CEC), electrical conductivity (EC), pH (H 2 O and KCl), phosphorus (using Bray method), nitrogen (NO 3 − ), sulfur (SO 4 2 − ), and extract- able K + , Mg 2 + , Ca 2 + , and Na + . A total extract of 29 metals was done per composite sample. Additionally, particle size distribution was conducted to determine the soil texture. Red list assessments of the species indigenous to South Africa were taken from Raimondo et al. (2009). However, the Namibian endemics, namely Commicarpus decipiens Meilke, C. fallacissimus (Heimerl) Heimerl ex. Obermeyer, Schweickerdt and I. Verdoorn and C. squarrosus (Heimerl) Standl. were assessed for the fi rst time according to the criteria of the World Conservation Union IUCN (2001). Commicarpus species are all perennial, but two distinct growth forms are discernable. Commicarpus fallacissimus , C. pilosus and C. squarrosus are semi-woody, sub-shrubs of 0.6 – 1.0 m high (Fig. 1a), while C . chinensis subsp. natalensis , C . decipiens , C . helenae var. helenae , C . pentandrus and C . plumbagineus var. plumbagineus are herbaceous forbs with procumbent, decumbent or scrambling stems, or sometimes upright (Fig. 1b). Younger plants of C. fallacissimus and C. pilosus are, however, often herbaceous forbs, but tend to develop a semi-woody, suffrutescent growth form with age. The shape of the leaves is variable (Fig. 2) and three groups are evident. The leaves of C. chinensis subsp. natalensis , C. helenae var. helenae , C. pentandrus and C. plumbagineus var. plumbagineus are trian- gular (cordate, ovate and deltoid), those of C. pilosus and C. squarrosus are roundish (orbicular and ovate) and those of C. fallacissimus and C. decipiens are elongated with a roundish base (lanceolate-ovate). Meikle (1978) stated that all the Commicarpus species are super fi cially similar in growth form and foliage, and the southern Africa species considered here are also not easily distinguishable in the fi eld despite the slight variations in habit and leaf shape discussed above. Vegetative characters therefore do not provide evidence on which to base a classi fi cation system. The in fl orescence in Commicarpus is an umbel, sometimes with up to four whorls together in the same in fl orescence. The peduncles are 20 – 150 mm long (Table 1). The fl owers of Commicarpus are infundibiliform (Fig. 3). The fl owers can be divided into two parts, an upper petaloid part and a distinct lower, coriaceous part (Fig. 4). The upper petaloid part has white, pink or purple fl avonoid pigmentation and is 2 – 17 mm long (Table 1). The lower, coriaceous part of the fl ower is 2 – 7 mm long and can be cylindrical ( C. chinensis subsp. natalensis , C. fallacissimus and C. plumbagineus var. plumbagineus ), clavate ( C. decipiens and C. pentandrus ) or elliptic ( C. helenae var. helenae , C. pilosus and C. squarrosus ). The lower part of the fl ower has ten narrow, longitudinal grooves with either fi ve ( C. helenae var. helenae , C. pentandrus , C. pilosus and C. squarrosus ) or ten ( C. fallacissimus and C. plumbagineus var. plumbagineus ) prominent glands around the apex, with less prominent glands scattered over the surface further below (Table 1). On ...